Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F290/00—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups
  • C08F290/02—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups on to polymers modified by introduction of unsaturated end groups
  • C08F290/06—Polymers provided for in subclass C08G
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F265/00—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00
  • C08F265/04—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00 on to polymers of esters
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F265/00—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00
  • C08F265/04—Macromolecular compounds obtained by polymerising monomers on to polymers of unsaturated monocarboxylic acids or derivatives thereof as defined in group C08F20/00 on to polymers of esters
  • C08F265/06—Polymerisation of acrylate or methacrylate esters on to polymers thereof
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F290/00—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups
  • C08F290/02—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups on to polymers modified by introduction of unsaturated end groups
  • C08F290/06—Polymers provided for in subclass C08G
  • C08F290/061—Polyesters; Polycarbonates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F299/00—Macromolecular compounds obtained by interreacting polymers involving only carbon-to-carbon unsaturated bond reactions, in the absence of non-macromolecular monomers
  • C08F299/02—Macromolecular compounds obtained by interreacting polymers involving only carbon-to-carbon unsaturated bond reactions, in the absence of non-macromolecular monomers from unsaturated polycondensates
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
  • C08K5/00—Use of organic ingredients
  • C08K5/16—Nitrogen-containing compounds
  • C08K5/34—Heterocyclic compounds having nitrogen in the ring
  • C08K5/3467—Heterocyclic compounds having nitrogen in the ring having more than two nitrogen atoms in the ring
  • C08K5/3477—Six-membered rings
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
  • C08L51/003—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J151/00—Adhesives based on graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Adhesives based on derivatives of such polymers
  • C09J151/003—Adhesives based on graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Adhesives based on derivatives of such polymers grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
  • C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
  • C09J133/04—Homopolymers or copolymers of esters
  • C09J133/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
  • C09J133/08—Homopolymers or copolymers of acrylic acid esters
• • C09J2201/606—
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J2301/00—Additional features of adhesives in the form of films or foils
  • C09J2301/30—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier
  • C09J2301/302—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J2433/00—Presence of (meth)acrylic polymer
• • C09J7/0217—
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J7/00—Adhesives in the form of films or foils
  • C09J7/30—Adhesives in the form of films or foils characterised by the adhesive composition
  • C09J7/38—Pressure-sensitive adhesives [PSA]
  • C09J7/381—Pressure-sensitive adhesives [PSA] based on macromolecular compounds obtained by reactions involving only carbon-to-carbon unsaturated bonds
  • C09J7/385—Acrylic polymers
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer
  • Y10T428/2809—Web or sheet containing structurally defined element or component and having an adhesive outermost layer including irradiated or wave energy treated component
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer
  • Y10T428/2852—Adhesive compositions
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T428/00—Stock material or miscellaneous articles
  • Y10T428/28—Web or sheet containing structurally defined element or component and having an adhesive outermost layer
  • Y10T428/2852—Adhesive compositions
  • Y10T428/2878—Adhesive compositions including addition polymer from unsaturated monomer
  • Y10T428/2891—Adhesive compositions including addition polymer from unsaturated monomer including addition polymer from alpha-beta unsaturated carboxylic acid [e.g., acrylic acid, methacrylic acid, etc.] Or derivative thereof

Definitions

• the invention relates to a mixture comprising
• the invention relates in particular to the use of the mixture as a pressure-sensitive adhesive.
• pressure-sensitive adhesive use is made inter alia of solvent-free polyacrylates or aqueous polyacrylate dispersions.
• the desire is therefore for solvent-free pressure-sensitive adhesives.
• Radiation-crosslinkable polymers and their use as an adhesive are known, for example from EP-A-246 848 or EP-A-377 199.
• PSAs radiation-crosslinkable pressure-sensitive adhesives
• Adhesion sticking to the substrate
• cohesion are divergent performance properties. Measures which bring about an improvement in the adhesion generally lead at the same time to a deterioration in the cohesion, and vice versa.
• the desire is therefore for measures which improve both the cohesion and the adhesion, but at least do not improve one of the two properties at the expense of the other. Also of importance is a high level of thermal stability on the part of the adhesive bond; that is, the bond should withstand mechanical loads even at relatively high temperatures. Particularly in the case of industrial applications, and especially with adhesive assembly tapes, high thermal stability is often critical to the use of an adhesive.
• Radiation-crosslinkable pressure-sensitive adhesives often have the drawback here that effective adhesion and cohesion are no longer achieved at high layer thicknesses.
• EP-A 1 578 823, EP-A 628 616 and EP-A 1 469 036 disclose mixtures of radiation-curable polyacrylates and oligomers containing two or more acrylic groups, and also disclose the use of these mixtures as pressure-sensitive adhesives.
• the mixture comprises
• the mixture of the invention comprises as essential constituents polymers A) and compounds B).
• the polymer A) is preferably synthesized from free-radically polymerizable compounds (monomers).
• the polymer is composed of at least 40%, more preferably at least 60% and very preferably at least 80% by weight of what are called principal monomers.
• the principal monomers are selected from C1-C20 alkyl (meth)acrylates, vinyl esters of carboxylic acids comprising up to 20 carbon atoms, vinylaromatics having up to 20 carbon atoms, ethylenically unsaturated nitrites, vinyl halides, vinyl ethers of alcohols comprising 1 to 10 carbon atoms, aliphatic hydrocarbons having 2 to 8 carbon atoms and 1 or 2 double bonds, or mixtures of these monomers.
• Examples include (meth)acrylic acid alkyl esters having a C1-C10 alkyl radical, such as methyl methacrylate, methyl acrylate, n-butyl acrylate, ethyl acrylate and 2-ethylhexyl acrylate.
• mixtures of the (meth)acrylic acid alkyl esters are also suitable.
• Vinyl esters of carboxylic acids having 1 to 20 carbon atoms are for example vinyl laurate, vinyl stearate, vinyl propionate, Versatic acid vinyl esters, and vinyl acetate.
• Suitable vinylaromatic compounds include vinyltoluene a- and p-methylstyrene, a-butylstyrene, 4-n-butylstyrene, 4-n-decylstyrene and, preferably, styrene.
• nitriles are acrylonitrile and methacrylonitrile.
• the vinyl halides are ethylenically unsaturated compounds substituted by chlorine, fluorine or bromine, preferably vinyl chloride and vinylidene chloride.
• vinyl ethers examples include vinyl methyl ether or vinyl isobutyl ether. Preference is given to vinyl ethers of alcohols comprising 1 to 4 carbon atoms.
• hydrocarbons having 2 to 8 carbon atoms and one or two olefinic double bonds mention may be made of butadiene, isoprene and chloroprene, ethylene or propylene.
• Preferred principal monomers are the C1 to C10 alkyl acrylates and methacrylates, especially C1 to C8 alkyl acrylates and methacrylates, the acrylates in each case being particularly preferred.
• the polymer may comprise further monomers, e.g., monomers having carboxylic acid, sulfonic acid or phosphonic acid groups.
• Carboxylic acid groups are preferred. Mention may be made, for example, of acrylic acid, methacrylic acid, itaconic acid, maleic acid or fumaric acid.
• monomers include, for example, monomers comprising hydroxyl groups, especially C1-C10 hydroxyalkyl (meth)acrylates, (meth)acrylamide, and monomers comprising ureido groups, such as ureido (meth)acrylates.
• monomers that may be mentioned include, moreover, phenyloxyethyl glycol mono(meth)acrylate, glycidyl acrylate, glycidyl methacrylate, and amino (meth)acrylates such as 2-aminoethyl (meth)acrylate.
• Monomers which in addition to the double bond carry further functional groups as well, e.g., isocyanato-, amino-, hydroxy-, amide- or glycidyl-, may have the effect, for example, of improving the substrate adhesion.
• Those suitable include, in particular, cyclic lactams such as N-vinylpyrrolidone or N-vinylcaprolactam.
• the polymer is preferably synthesized from at least 40%, more preferably at least 60% and very preferably at least 80% by weight of C1-C20 alkyl (meth)acrylates, especially the abovementioned alkyl (meth)acrylates.
• the polymer in question is preferably a polymer which is crosslinkable by irradiation with high-energy light, e.g., UV light, or electron beams.
• the polymer is crosslinkable thus if, for example, hydrogen protons can be detached from the main chain of the polymer photochemically, including in particular through the use of a photoinitiator or as a result of electron beams, thereby producing a free radical which is able to enter into further chemical reactions.
• the mixture preferably comprises a photoinitiator.
• the photoinitiator may comprise, for example, what are called ⁇ -splitters; that is, photoinitiators in which a chemical bond is cleaved to form 2 free radicals which initiate the further crosslinking or polymerization reactions.
• acylphosphine oxides LOCIRIN® products from BASF
• hydroxyalkylphenones e.g., IRGACURE® 184 hydroxyalkylphenones
• benzoin derivatives e.g., benzil derivatives, and dialkyloxyacetophenones.
• the compounds in question may be what are called H abstractors, which detach a hydrogen atom from the polymer chain; these are, for example, photoinitiators having a carbonyl group. This carbonyl group is inserted into a C—H bond to form a C—C—O—H moiety.
• the photoinitiator or at least one of the photoinitiators, if a mixture is used, is attached to the polymer A).
• the photoinitiator in question is a photoinitiator which is incorporated into the polymer chain by means of free-radical copolymerization.
• the photoinitiator preferably comprises an acrylic or (meth)acrylic group.
• Suitable copolymerizable photoinitiators are acetophenone derivatives or benzophenone derivatives which comprise at least one, preferably one, ethylenically unsaturated group.
• the ethylenically unsaturated group is preferably an acrylic or methacrylic group.
• the ethylenically unsaturated group may be attached directly to the phenyl ring of the acetophenone derivative or benzophenone derivative.
• the spacer group may comprise, for example, up to 100 carbon atoms.
• Suitable acetophenone derivatives or benzophenone derivatives are described for example in EP-A-346 734, EP-A-377 199 (1st claim), DE-A-4 037 079 (1st claim) and DE-A-3 844 444 (1st claim) and by this reference are also disclosed in the present application.
• Preferred acetophenone derivatives and benzophenone derivatives are those of the formula
• R11 stands for an organic radical having up to 30 carbon atoms
• R21 for a hydrogen atom or a methyl group
• R3 for an optionally substituted phenyl group or a C1-C4 alkyl group.
• the mixture of the invention comprises preferably 0.0001 to 0.5 mol, more preferably 0.0002 to 0.1, very preferably 0.003 to 0.01 mol of the photoinitiator, or of the molecule group which is active as a photoinitiator and is attached to the polymer, per 100 g of the sum by weight of A)+B).
• the polymer A) preferably has a K value of 10 to 100, in particular of 30 to 80, more preferably of 40 to 60, measured in tetrahydrofuran (1% strength solution, 21° C.).
• the K value according to Fikentscher is a measure of the molecular weight and viscosity of the polymer.
• the molar weight associated with the above K value range is far higher than the molar weight of the compounds B).
• the average molar weight (both the number-average and the weight average) of the polymer A) is generally at least twice and in particular at least 10 times as high as that of the compounds B).
• the glass transition temperature (Tg) of the polymer A) is preferably ⁇ 60 to +10° C., more preferably ⁇ 55 to 0° C., very preferably ⁇ 55 to ⁇ 10° C.
• the glass transition temperature of the polymer can be determined in accordance with customary methods such as differential thermoanalysis or differential scanning calorimetry (see, e.g., ASTM 3418/82, midpoint temperature).
• Polymers A) can be prepared by copolymerizing the monomeric components with the use of the customary polymerization initiators and also, where appropriate, of regulators, polymerization taking place at the customary temperatures in bulk, in emulsion, e.g., in water or liquid hydrocarbons, or in solution.
• the polymers are prepared by polymerizing the monomers in solvents (solution polymerization), particularly in solvents with a boiling range of 50 to 150° C., preferably from 60 to 120° C., using the customary amounts of polymerization initiators, which are generally 0.01% to 10%, in particular 0.1% to 4% by weight, based on the total weight of the monomers.
• Suitable solvents include in particular, alcohols, such as methanol, ethanol, n- and isopropanol, n- and isobutanol, preferably isopropanol and/or isobutanol, and hydrocarbons such as toluene and, in particular, benzenes with a boiling range of 60 to 120° C.
• alcohols such as methanol, ethanol, n- and isopropanol, n- and isobutanol, preferably isopropanol and/or isobutanol
• hydrocarbons such as toluene and, in particular, benzenes with a boiling range of 60 to 120° C.
• ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone
• esters such as ethyl acetate
• mixtures which comprise isopropanol and/or isobutanol in amounts of 5% to 95%, in particular of 10% to 80%, preferably of 25% to 60% by weight, based on the solution mixture used.
• Suitable polymerization initiators for solution polymerization include for example azo compounds, ketone peroxides and alkyl peroxides.
• the solvents can if appropriate be separated off under reduced pressure, in which case operation takes place at elevated temperatures, in the range of 100 to 150° C. for example.
• the polymers can then be used in the solvent-free state, i.e., as melts.
• Compounds B) are compounds containing ethylenically unsaturated, free-radically polymerizable groups (polymerizable group for short) and having a weight-average molecular weight, Mw, of less than 5000 g/mol.
• the key feature is that at least 10% by weight of the compounds B are compounds containing at least one nonaromatic ring system, referred to below as compounds B1.
• Suitable nonaromatic ring systems include cycloaliphatic ring systems and heterocyclic systems, especially those which as well as carbon contain nitrogen.
• Suitable cycloaliphatic ring systems include single ring systems, such as a cyclohexane ring, or else bicyclic or polycyclic ring systems, such as ring systems comprising two six-membered carbon rings, two five-membered carbon rings, or one six-membered carbon ring and one five-membered carbon ring; in that case it is possible for a further carbon bridge to be formed in each case between two C atoms of the ring system.
• Suitable compounds B1 containing cycloaliphatic ring systems and polymerizable groups are available under the trade name SARTOMER® or LAROMER®.
• heterocyclic ring system mention may be made in particular of the isocyanurate ring.
• Isocyanurates can be obtained by trimerizing monoisocyanates or polyisocyanates, especially diisocyanates. Other preparation methods are known as well, examples being those which start from isocyanuric acid.
• the isocyanurate ring is formed by a total of three isocyanate groups.
• one isocyanate group of the polyisocyanate or diisocyanate is part of the ring, while the other isocyanate groups are free and are available for further reactions.
• the free isocyanate groups can easily be reacted with compounds which comprise free-radically polymerizable groups.
• One very simple reaction, for example, is that with hydroxyalkyl acrylates.
• trimerized monoisocyanates the isocyanurate ring is formed from the three isocyanate groups present.
• the free-radically polymerizable groups are attached by reaction with suitable other functional groups of the monoisocyanates.
• Preferred isocyanurates are the isocyanurates of the customary diisocyanates.
• X is an aliphatic hydrocarbon radical having 4 to 15 carbon atoms, a cycloaliphatic or aromatic hydrocarbon radical having 6 to 15 carbon atoms or an araliphatic hydrocarbon radical having 7 to 15 carbon atoms.
• diisocyanates examples include tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 1,4-diisocyanatocyclohexane, 1-isocyanato-3,5,5-trimethyl-5-isocyanatomethyl-cyclohexane (IPDI), 2,2-bis(4-isocyanatocyclohexyl)propane, trimethylhexane diisocyanate, 1,4-diisocyanatobenzene, 2,4-diisocyanatotoluene, 2,6-diisocyana-totoluene, 4,4′-diisocyanatodiphenylmethane, 2,4′-diisocyanatodiphenylmethane, p-xylylene diisocyanate, tetramethylxylylene diisocyanate (TMXDI), the isomers of bis(4-iso
• Particularly preferred compounds B1 are the above isocyanurates which comprise (meth)acrylic groups through reaction with suitable reactive compounds, in particular with hydroxyalkyl (meth)acrylates.
• compounds B1 may also comprise aromatic ring systems or aliphatic molecule groups.
• At least 7% by weight, in particular at least 10% by weight, with very particular preference at least 15% by weight, and in one particular embodiment at least 20% by weight of compounds B1, based on their molar mass, is composed, with particular preference, of carbon or nitrogen atoms which are part of a ring system.
• Preferably not more than 70% by weight, more preferably not more than 50% by weight, or not more than 45% by weight, and very preferably not more than 35% by weight, of compounds B1 is composed of carbon or nitrogen atoms which are part of a ring system.
• Suitable compounds B1 having an isocyanurate ring and polymerizable groups are likewise available under the trade names SARTOMER® or LAROMER®.
• Compounds B may comprise further compounds as well as compounds B1.
• At least 30% by weight, more preferably at least 50% by weight, very preferably at least 80% by weight, and in particular 100% by weight of the compounds B are compounds B1.
• Suitable compounds B) include other compounds besides B1.
• (meth)acrylate compounds mention may be made of (meth)acrylic esters and especially acrylic esters of polyfunctional alcohols, particularly those which other than the hydroxyl groups comprise no further functional groups, or ether groups if any at all.
• alcohols are, for example, difunctional alcohols, such as ethylene glycol, propylene glycol, and their representatives with higher degrees of condensation, for example such as diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, etc., butanediol, pentanediol, hexanediol, neopentyl glycol, alkoxylated phenolic compounds, such as ethoxylated and/or propoxylated bisphenols, cyclohexanedimethanol, trifunctional and higher polyfunctional alcohols, such as glycerol, trimethylolpropane, butanetriol, trimethylolethane, pentaerythritol, ditrimethylol
• the alkoxylation products are obtainable in known manner by reacting the above alcohols with alkylene oxides, especially ethylene oxide or propylene oxide.
• the degree of alkoxylation per hydroxyl group is preferably 0 to 10, i.e., 1 mol of hydroxyl group can be alkoxylated preferably with up to 10 mol of alkylene oxides.
• polyester (meth)acrylates which are the (meth)acrylic esters of polyesterols.
• polyesterols examples include those as may be prepared by esterifying polycarboxylic acids, preferably dicarboxylic acids, with polyols, preferably diols.
• the starting materials for such hydroxyl-containing polyesters are known to the skilled worker.
• dicarboxylic acids use may be made preferably of succinic acid, glutaric acid, adipic acid, sebacic acid, o-phthalic acid, their isomers and hydrogenation products and also esterifiable derivatives, such as anhydrides or dialkyl esters of said acids.
• Suitable polyols include the abovementioned alcohols, preferably ethylene glycol, propylene 1,2- and 1,3-glycol, butane-1,4-diol, hexane-1,6-diol, neopentyl glycol, cyclohexanedimethanol, and also polyglycols of the ethylene glycol and propylene glycol type.
• Polyester (meth)acrylates can be prepared in a plurality of stages or else in single-stage form, as described for example in EP 279 303, from acrylic acid, polycarboxylic acid, and polyol.
• compounds B) may be, for example, epoxy (meth)acrylates or urethane (meth)acrylates.
• Epoxy (meth)acrylates are, for example, those as obtainable by reacting epoxidized olefins or poly- and mono- or diglycidyl ethers, such as bisphenol A diglycidyl ether, with (meth)acrylic acid.
• Urethane (meth)acrylates are, in particular, reaction products of hydroxyalkyl (meth)acrylates with poly- and/or diisocyanates (see likewise R. Holmann, U.V. and E.B. Curing Formulation for Printing Inks and Paints, London 1984).
• Compounds B) are preferably liquid at 21° C. and 1 bar; if the compounds are solid at 21° C. and 1 bar they ought to dissolve well in the polymer A).
• the viscosity of the compounds B, or of the mixture of the compounds B is preferably 0.01 to 50 Pas, more preferably 0.04 to 10 Pas at 23° C., 1 bar, measured in accordance with DIN EN ISO 3219; with very particular preference the viscosity is 0.04 to 2 and in particular 0.04 to 1 Pas.
• the weight-average molecular weight Mw of the compounds B is preferably below 5000, more preferably below 3000 g/mol (determined by gel permeation chromatography with polystyrene as standard and tetrahydrofuran as eluent). With very particular preference it is below 2000 g/mol.
• compounds B have 1 to 5, preferably 1.5 to 3, more preferably 2 to 3, in one particular embodiment 2 to 2.5 polymerizable groups per molecule.
• the mixture of A) and B) is suitable as a binder for pressure-sensitive adhesives, for example the weight fraction of A) being preferably not more than 99%, more preferably not more than 95% and preferably at least 30%, more preferably at least 50% or at least 60% by weight.
• the weight fraction of B) is preferably not more than 70%, more preferably not more than 50% or not more than 40%, and preferably at least 1%, more preferably at least 5%, by weight.
• Suitable weight ranges of A) and B) are in particular:
• the mixture of A) and B) can be prepared by customary methods.
• polymer A) is heated, to temperatures for example between 50 and 130° C., and compounds A), together if appropriate with further additives, are incorporated with stirring.
• the mixture is suitable as a binder for pressure-sensitive adhesives.
• the pressure-sensitive adhesives may be composed solely of the mixture of A) and B).
• hotmelt PSAs in which water or other solvents, from the solution polymerization of A), for example, are present, if at all, in small amounts, and which are applied from the melt.
• the pressure-sensitive adhesive, or hotmelt PSA comprises less than 5 parts, in particular less than 2 parts or 1 part by weight of water and/or solvent per 100 parts by weight of the sum by weight of A) and B).
• the pressure-sensitive adhesive, or hotmelt PSA is substantially free from water and other solvents.
• the pressure-sensitive adhesive comprises at least one photoinitiator (see above).
• the photoinitiator is not a photoinitiator which is attached to the polymer, the photoinitiator may be added at any time to the mixture of A) and B) or to the actual components A) or B).
• Further additives which may be added to the pressure-sensitive adhesive are, for example, fillers, dyes, flow control assistants and, in particular, tackifiers (tackifying resins).
• Tackifiers are, for example, natural resins, such as rosins and their derivatives formed by disproportionation or isomerization, polymerization, dimerization or hydrogenation. They may be in their salt form (with monovalent or polyvalent counterions (cations), for example) or, preferably, in their esterified form. Alcohols which can be used for the esterification may be monohydric or polyhydric. Examples are methanol, ethanediol, diethylene glycol, triethylene glycol, 1,2,3-propanethiol and pentaerythritol.
• hydrocarbon resins e.g., coumarone-indene resins, polyterpene resins, hydrocarbon resins based on unsaturated CH compounds, such as butadiene, pentene, methylbutene, isoprene, piperylene, divinylmethane, pentadiene, cyclopentene, cyclopentadiene, cyclohexadiene, styrene, a-methylstyrene, vinyltoluene.
• unsaturated CH compounds such as butadiene, pentene, methylbutene, isoprene, piperylene, divinylmethane, pentadiene, cyclopentene, cyclopentadiene, cyclohexadiene, styrene, a-methylstyrene, vinyltoluene.
• polyacrylates which have a low molar weight.
• these polyacrylates have a weight-average molecular weight Mw of below 30 000.
• the polyacrylates are composed preferably of at least 60%, in particular at least 80%, by weight of C1-C8 alkyl (meth)acrylates.
• Preferred tackifiers are natural or chemically modified rosins. Rosins are composed predominantly of abietic acid or derivatives of abietic acid.
• the amount by weight of the tackifiers is for example 5 parts to 100 parts by weight, more preferably 10 parts to 50 parts by weight, based on 100 parts by weight of the sum by weight of A)+B).
• the pressure-sensitive adhesives are preferably used as hotmelt pressure-sensitive adhesives; that is, they are applied from the melt to the desired backings.
• pressure-sensitive or hotmelt adhesives of the invention are suitable for producing self-adhesive articles, such as labels, adhesive tapes or adhesive sheets, examples being protective films.
• the self-adhesive articles are generally composed of a backing and a layer of the adhesive applied to one or both sides, preferably one side.
• the backing material may be, for example, paper, polymeric films of polyolefins or PVC.
• the self-adhesive articles are produced in particular by applying the pressure-sensitive adhesive to the backing and then effecting crosslinking with UV light or electron beams.
• a particular advantage of the invention is that self-adhesive articles can be produced at high application rates, i.e. with thick pressure-sensitive adhesive layers.
• the application rate may amount in particular to 10 to 300 g, preferably 10 to 150 g, and generally often 20 to 80 g per square meter of backing.
• the coated backing is exposed to high-energy light, preferably UV light, in order to achieve the desired crosslinking.
• the radiation energy can amount for example to 10 mJ/cm2 to 1 500 mJ/cm2 of irradiated area.
• Preferred self-adhesive articles are labels or adhesive assembly tapes.
• the protective film is intended to protect articles in the course of transit or storage.
• the protective films can be pulled off again from the article by hand without residue.
• the self-adhesive articles are suitable for a very wide variety of substrates.
• the substrates may, for example, be of metals, paper, card, wood, plastics, etc.
• thermal stability is also improved, i.e., the adhesive bonds hold even at high temperatures.
• the mixtures or pressure-sensitive adhesives of the invention are also particularly suitable for adhesive assembly tapes which find use in the industrial production of, for example, motor vehicles.
• a polymerization apparatus composed of a glass reactor with heating/cooling circuit, stirrer, thermocouple, reflux condenser, nitrogen inlet and metering vessels is charged under a gentle stream of nitrogen with 364 g of methyl ethyl ketone (MEK) and this initial charge is heated to 80° C. 100 g of a monomer mixture consisting of 94.8% n-butyl acrylate, 5% acrylic acid and 0.18% of a photoinitiator of the formula I are added. When 80° C. have been regained, 4.9 g of an initiator solution of 13.07 g tert-butyl perpivalate and 86.7 g of MEK are added and initial polymerization takes place for 10 minutes.
• MEK methyl ethyl ketone
• a polymerization apparatus composed of a glass reactor with heating/cooling circuit, stirrer, thermocouple, reflux condenser, nitrogen inlet and metering vessels is charged under a gentle stream of nitrogen with 456 g of methyl ethyl ketone (MEK) and this initial charge is heated to 80° C. 120 g of a monomer mixture consisting of 94.73% n-butyl acrylate, 5% acrylic acid and 0.27% of a photoinitiator of the formula I are added. When 80° C. have been regained, 5.4 g of an initiator solution of 19.3 g tert-butyl perpivalate and 88.8 g of MEK are added and initial polymerization takes place for 10 minutes.
• MEK methyl ethyl ketone
• polymer solution from Example 4 561 g of polymer solution from Example 4 are admixed with 0.018 g of 4-hydroxy Tempo and freed from the solvent under reduced pressure and, in the course of that procedure, it is heated to 135° C.
• the polymer is cooled to 110° C. and admixed with 35 g of SARTOMER® SR 368 monomer, preheated to 80° C., and 15 g of LUCIRIN® TPO-L initiator, and the mixture is stirred for a further hour.
• polymer solution from Example 1 536 g of polymer solution from Example 1 are admixed with 0.0018 g of 4-hydroxy Tempo and the mixture is freed from the solvent under reduced pressure and in the course of that same procedure is heated to 135° C.
• the polymer is cooled to 110° C., admixed with 35.14 g of hexamethylene diacrylate, preheated to 80° C., and with 15 g of LUCIRIN® TPO-L initiator, stirred for 1 hour more, and then discharged.
• the mixtures were used without further additions as hot-melt pressure-sensitive adhesives. They were heated to 95° C. and coated directly on to a polyethylene terephthalate (PETP) film by means of a bar coater (adhesive application rate 60 g dry/m2).
• PETP polyethylene terephthalate
• test strips 25 mm wide.
• test strips were adhered with a bonded area of 25 mm2 to the steel test surface (Afera steel), rolled on once with a 1 kg roller, stored for 10 minutes (under standard conditions, 50% relative humidity, 1 bar, 23° C.) and then loaded in suspension with a 1 kg weight (under standard conditions).
• the measure of the shear strength was the time taken for the weight to fall off; in each case the average from 5 measurements was calculated.
• peel strength (adhesion) a 2.5 cm wide test strip was bonded to the steel test surface in each case and rolled on once with a 1 kg roller. It was then clamped by one end into the upper jaws of a stress/strain testing apparatus. The adhesive strip was pulled from the test surface at 300 mm/min and an angle of 180°, i.e., the test strip was bent over and pulled off parallel to the metal test plate, and the force required to accomplish this was measured. The measure of the peel strength was the force, in N/2.5 cm, which resulted as the average value from five measurements.
• the peel strength was determined 24 hours after bonding. After this time the bond strength has developed fully.
• the samples were prepared as for the shear test, adhered to steel, but rolled on 4 times using a roller weighing 2 kg, and stored under standard conditions for 16 hours. The samples were then suspended in a controlled-climate drying cabinet and loaded with 1 kg, and the temperature was raised in stages of 0.5° C./min. The measure of the heat resistance is the temperature at which the weight falls off. The figure reported is the average value from three measurements.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Adhesives Or Adhesive Processes (AREA)
• Adhesive Tapes (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
• Polymerisation Methods In General (AREA)
• Graft Or Block Polymers (AREA)
• Macromonomer-Based Addition Polymer (AREA)

Applications Claiming Priority (4)

Publications (2)

Family

ID=38895966

Family Applications (1)

Country Status (6)

Families Citing this family (17)

Citations (24)

• 2007
  • 2007-10-29 US US12/441,670 patent/US9725549B2/en active Active
  • 2007-10-29 ES ES07821978T patent/ES2376773T3/es active Active
  • 2007-10-29 AT AT07821978T patent/ATE539094T1/de active
  • 2007-10-29 WO PCT/EP2007/061623 patent/WO2008049932A1/de active Application Filing
  • 2007-10-29 EP EP07821978A patent/EP2087021B1/de active Active
  • 2007-10-29 JP JP2009533878A patent/JP5665318B2/ja not_active Expired - Fee Related

Patent Citations (36)

Non-Patent Citations (9)

Also Published As

Similar Documents

Legal Events